Apparatus for determining the contour and position of obstructions in wells



Feb. 25; 1958 5T0 E5 F. X 2,824,378 APPARATUS FOR DETERMINING T CONTOUB; AND POSITION OF OBSTRUCTIONS Filed June 12, 1953 L/O/Ifl F. sic/(; INVENTOR.

BY I ma ATTORNEY United States Patent APPARATUS FOR DETERMINING THE CONTOUR AND POSITION OF OBSTRUCTIONS lN WELLS John F. Stokes, Corpus Christi, Tex., assignor to Petroleum Recovery Engineering Corporation, a corporation of Delaware Application June 12, 1953, Serial No. 361,151

1 Claim. (Cl. 33-175) This invention relates to apparatus for determining the contour and position of obstructions in wells, and more particularly to means adapted to be lowered into a well bore to engage lost objects or the like therein whereby the contour and position of such object in the well may be ascertained.

While not limited to such use the invention finds particular application in connection with the drilling and operation of wells such as oil wells and provides a means for conveniently determining the position and character of obstructions therein. In the drilling and operation of oil wells numerous obstructions arefrequently encountered in the bore of the well which interfere with the operations being performed and which must be removed before the drilling or other operation can be resumed. Such obstructions often take the form of lost objects, collapsed portions of well casing, caved-in formation, inwardly projecting burs in the well casing, stuck objects, various kinds of junk in the bottom of the bore and the like, whose exact position and contour in the well bore is unknown.

Heretofore it has been proposed to locate and determine the position of such objects by lowering into the well bore a body of relatively soft material such as wax, soap, or the like which may readily be impressed with the contour of the obstruction by engagement therewith so that upon removal of the body the shape and position of the obstruction can be determined. It has also been proposed to employ for this purpose other more durable materials such as blocks of lead or other soft metal capable of bearing an impression of the obstruction. Soft materials such as, soap, wax, and the like, are adversely effected by changes in temperature such as frequently obtain in wells and are easily deformed so that the impression obtained by contact with the obstruction is likely to be destroyed in removing the body from the well, and in the case of a block of metal the impression obtained is often too shallow to accurately indicate the shape and position of the obstruction.

The present invention has for an important object the overcoming of the above disadvantages by the provision of means which is capable of receiving and retaining an impression by engagement with an object in a well bore whereby the position of the object in the bore and its contour may be accurately determined.

Another object of the invention is to provide impression receiving means having portions which are movable upon contact with an object in the bore of a well to form an impression by which both the position and contour of the object may be accurately indicated.

Another object of the invention is the provision of an impression taking device having numerous movable portions positioned to encounter an object in the bore of a well and which are disposed to be moved by engagement with the object to assume positions forming an impression indicating the contour and position of the object.

A still further object of the invention is to provide an impression taking device of the character referred to 2,824,378 Patented Feb. 25, 1958 which is of simple design and which may be easily and economically manufactured.

Other important objects and advantages of the invention will best be understood from the following detailed description, constituting a specification of the same, when taken in conjunction with the annexed drawings, wherein The single figure in the drawing is a vertical, central, cross-sectional view of the device.

A preferred embodiment of the invention is illustrated in the drawings, wherein a tubular housing 124 is provided, which has an internal annular groove 126 near its upper end and is formed with an inwardly extending annular projection 128 at its lower end. A head member 130 is positioned on the upper end of the body 124, and is secured to the lower end of a tubing string 62 by means of a pin 132, or other suitable fastening means, and this head member is provided with a passageway 134 opening exteriorly of the head, and in communication with the interior of the tubing through a suitable opening 136 therein, whereby well fluid may pass from the tubing outwardly through the head and into the well bore.

Within the body there is a plunger 138, which is movable longitudinally therein, and which extends upwardly into the lower end of the tubing, to which it is secured by means of a shear pin 140, or the like, which pin may be sheared to permit removal of the tubing in the event that the body should become stuck in the well bore. An internal snap ring 142 is seated in the internal groove 126 and extends into the interior of the body in engagement with the upper face of the plunger 138 whereby the body is supported from the tubing. Suitable openings 144 may be provided in the body 124, for the purpose of equalizing the pressure on the interior of the housing with that on the exterior thereof.

The housing 124 also has an internal annular groove 146 therein, and between this groove and the internal projection 128 at the lower end of the body a pair of spaced plates 148 and 150 are positioned, which plates are held in spaced apart relation by suitable friction material, such as rubber or the like 152 positioned between the plates. The plates are held in position by means of a snap ring 154, seated in the internal groove 146.

The plates 148 and 150 are perforated, and a plurality of rods 156 extend through corresponding openings in the plate, and through the friction material 152, so that these rods are movable longitudinally in the body, but such longitudinal movement will be resisted by the friction of the friction material 152.

The invention is employed by lowering the same into a well bore attached to the tubing string 62, the fingers 156 being positioned so that their lower ends are in a single horizontal plane beneath the lower end of the body, and the device being lowered in this condition into the bore of the well to engage an obstruction therein. When the fingers 156 engage the obstruction they will be moved longitudinally in the body in conformity with the contour of the obstruction, so that upon removal of the body from the bore the contour and position of the obstruction can be easily observed. Should it be desirable to reset the fingers 156 after removal of the tool from the well the body may be moved longittidinally with respect to the tubing 62 by removing the pin 132, and upon downward movement of the plunger 138 in the body the plunger will engage the upper ends of the fingers 156 to move them downwardly to reposition the lower ends of the fingers in a single plane. In this manner the fingers may be reset for the next operation of the device.

It will thus be seen that the invention, as described above, provides an impression taking device of simple design, which is easily applied to any suitable type of support for lowering into the bore of the well, and by which the position and shape of an obstruction in the well may be accurately determined, so that the proper tools and steps to be taken for the removal of the obstruction may be worked out, thus substantially reducing the time and labor consumed in such operations.

While the invention has beendisclosed in connection with a certain specific embodiment of the same, it will be understood that this is intended by way of illustration only, and that numerous changes can be made in the construction and arrangement of the various parts, without departing from the spirit of the invention or the scope of the appended claim.

Having thus clearly shown and described the invention what is claimed as new and desired to secure by Letters Patent is:

A device for determining the contour and position of an object in a Well comprising, a tubular body whose lower end is open, means forming a removable'connection between the body and a support exetnding into the upper end of the body for lowering the body with the support into a well bore, said means being removable to permit relative longitudinal movement of the support and body, a plurality of elongated elementsmounted within the body for longitudinal movement relative thereto and whose lower ends are positioned for engagement with an object in the well bore to move said elements longitudinally in accordance with the contour and position of the object, means in the body in frictional engagement with the elements to yieldingly resist longitudinal movement of the elements, and means movably mounted in vthe body for longitudinal movement therein in position to engage the upper ends of said elements and connected to said support for movement with the support to move the elements downwardly in the body upon downward movement of the support relative to the body.

References Cited inthe. file of this patent UNITED STATES PATENTS Germany ....L. Dec. 3, 1918 

